Anti-glitch induced by collision of a solid body with the magnetar 1E 2259+586

Y. F. HuangCollaborator: J. J. Geng

Nanjing University

Outline

1. Background: glitches

2. Anti-glitch from 1E 2259+586

3. Our model: collision event

4. Discussion

Espinoza et al. 2011 MNRAS

30 years timing history of PSR B1930+22

Espinoza et al. 2011 MNRAS

4 large glitches in the Crab pulsar

Espinoza et al. 2011 MNRAS

More glitches

Espinoza et al. 2011 MNRAS

Glitches of Magnetars RXS J170849.0-400910 and 1E 1841-045

Dib et al. 2008, ApJ

]1[)()( /00 QQett t

Shapiro & Teukolsky 2004

Explanations for glitches

The origin is still debated:• Superfluidity: interaction of quantized

neutron vortex lines with the neutron-rich nuclear clusters in the inner crust (Pines & Alpar 1985; Negele & Vautherin 1973; Pizzochero 2011)

• Crust-cracking events (Ruderman et al. 1998) ?

Pines & Alpar 1985

http://www.eskesthai.com/search/label/Bose%20Condensate

Outline

1. Background: glitches

2. Anti-glitch from 1E 2259+586

3. Our model

4. Discussion

The Magnetar 1E2259+586

• P=6.979 s (v = 0.143 Hz)

•

•

• d = 4+/-0.8 kpc

• A few history glitches observed

sHz /108.9 15

GB 130 109.5

1E 2259+586. Credit: ESA/XMM-Newton/M. Sasaki et al.

History glitches: 2002 outburst

2002 outburst

On June 18

Woods et al. 2004

History glitches: 9 years overview

Icdem et al. 2012

2002

glitch

Possible micro anti-glitch?

An anti-glitch in April 2012

Archibald et al. 2013, Nat.

Archibald et al. 2013, Nat.

Timing events in around April 2012

Model 1:

Model 2:

Hz810)6(5.4

sHz /10)2(7.2 14

Hz810)7(6.3

sHz /10)2(6.2 14

Hz810)1(9

sHz /10)4(3.1 14

Hz810)8(8.6

sHz /10)4(1.1 14

+

+

x2=45.4/44

x2=38.1/44

Archibald et al. 2013, Nat.

Model 1:Hz810)6(5.4

sHz /10)2(7.2 14

Hz810)7(6.3

sHz /10)2(6.2 14+ x2=45.4/44

A hard X-ray burst: Exb=1.1e38 erg (36ms, Fermi/GBM,10-1000keV)

An X-ray afterglow: Ex=2.1e41 erg (2-10 keV, Fx ~ t-0.38)

Pulse profile: changed

Foley et al. 2012

Possible models for anti-glitches

Internal mechanisms• Internal superfluid spins slower than the crust? (Thompson et al. 2000; Garcia & Ranea-Sandoval 2014, arXiv:1402.0848)

External mechanisms• Strong outflows (Tong 2013)

• Sudden twisting of magnetic fields (Lyutikov 2013)

• Accretion disk of retrograde matter (Katz 2013; Ouyed et al. 2013)

Cannot explain the rarity

or

Not a sudden glitch, cannot explain the outburst.

Outline

1. Background: glitches

2. Anti-glitch from 1E 2259+586

3. Our model

4. Discussion

Our model: collision of a solid body with the magnetar

Huang & Geng, ApJ, 2014, 782, L20 (arXiv:1310.3324)

Our model: collision of a solid body with the magnetar

nspln41

x /~101.2~ RmGMergE s

gm 21pl 101.1~

)(22 cplplc IpVmI

cnspl 22 IpGMm

,170mp kmb 6.2

Huang & Geng, ApJ, 2014, 782, L20 (arXiv:1310.3324)

Colgate & Petschek 1981

Our model: collision process

gm 21pl 101.1~

3pl /8 cmg kmr 70pl

.cm102.1)/( 103/1ns

2plplb SGMrR

broken up distance:

36ms ms122

3

22/1

b

nspla

R

GMrt

Collision duration: (Colgate & Petschek 1981)

Huang & Geng, ApJ, 2014, 782, L20 (arXiv:1310.3324)

Consistency with observations

• Association with an outburst• Duration of the outburst (36ms)• Energy release in the afterglow (2.1e41 erg) • Amplitude of the anti-glitch ( )Hz810)6(5.4

Huang & Geng, ApJ, 2014, 782, L20 (arXiv:1310.3324)

Credit: NASAhttp://www.futuretimeline.net/blog/2013/06/2.htm#.U9Mhi7flpQI

Outline

1. Background: glitches

2. Anti-glitch from 1E 2259+586

3. Our model

4. Discussion

Discussion: more collision events are possible

gm 21pl 101.1~

,170mp

kmb 6.2

cmM 4.1cm10G10cm10cm g 8

107.19/1

Θ

ns

3/4

6ns

9/4

140

9/2

6

pl

9/2

3

pl7

MRBrb

The capture radius could be as large as: 20Rns --- 80 Rns

Tremaine & Zytkow 1986, ApJ

Collision possibility

• Asteroids disturbed by other planets?• Oort-like cloud objects scatterd toward the NS?• Collision of planets, generating small bodies?• Neutron star escaping its original planet system?• ……

• Collision rate: 1 per 5,000 --- 3e7 years for a single NS. (Mitrofanov &

Sadgeev 1990)

Collision-induced glitches/anti-glitches

• Collision can produce either glitches or anti-glitches• They can be either radiatively active or inactive• Unlikely show any periodicity for a single NS• More likely happen in young pulsars than old ones• May have already been observed previously

• A new method to probe the capture events of neutron stars.

Thank You!